1. Field of the Invention
The present invention relates to a topical formulation for preventing or treating acne through antimicrobial activity against acne-causing bacteria, Propionibacterium acnes, inhibition of excess production of sebum by inhibition of 5α-reductase, inhibition of comedo, keratolysis and anti-inflammatory action, which comprises extract obtained from at least one oriental medicine selected from the group consisting of Cavalia gladiata, Biota orientalis and Coptis chinensis. 
2. Description of the Related Technical Field
Acne is developed in teen-agers at an incidence of 90% but also found in adults of in their twenties- or thirties at rare intervals. Acne (or acne vulgaris) is a chronic inflammatory disease or a disorder developed at sebaceous gland and hair follicle, of which etiopathology includes excess secretion of sebum, dyskeratinization of epidermis of hair follicle, overgrowth of anaerobic skin-colonizing bacterium, Propionibacterium acnes and other causes. Acne is generally found on face, chest, back, neck and brachium, the most noticeable parts of skin, and characterized as comedo, pustule, lupus, petty knob or scar.
At the early stage of acne, the excessively-secreted sebum is accumulated in hair follicle and the hair follicle is in turn swelled due to pressure of sebum, resulting in the occurrence of comedo, wherein those with closed hair follicle become white acnes (closed comedo) while those with slight-opened hair follicle tip become black acnes (open comedo). Upon further development of acne, bacteria elicit inflammation that contributes to the occurrence of two different types of symptoms: a papule type showing reddish skin with petty comedo and a pustule type showing pus. There are a few differences between acnes of teen-agers and adults, as summarized in Table 1.
TABLE 1Differences between Acnes of Teen-agers and AdultsClassificationTeen-ager acnesAdult acnesLocation ofBrow, entire face, anyTend to position at the lowerOccurrenceparts where sebaceouspart of face such as cheek,gland existsgirth of mouth and jaws ascompared to teen-agersSeason ofSpring and Summer inYear-round occurrenceOccurrenceassociation withwithout seasonal outbreakactivation of sebaceousglandSymptomsDevelopedDeveloped simultane-ouslysimultaneously withwith skin dryness, repetitionexcess sebum,of petty acne boss (shotappearance ofappearance type), slowpetty comedo at theprogress in treatment, vestigeactivated part of sebumof acnes remainedsecretionCausesPhysical instabilityClosely related to physicalduring growth periodand mental conditions ofbody such as hormonalimbalance, insufficient sleep,fatigue, stress andmenstruation. Low relationto skin conditions
As shown in Table 1, the teen-ager acnes are developed at the entire parts of brow and face in spring and summer when the secretion of sebum is active and they are very likely to develop in oily skins. In contrast, the adult acnes are apt to develop throughout the year at restricted parts and are known to have little or no relation with lipid content. The development is affected by physical and mental conditions of body such as hormonal imbalance, stress, irregular dietary habits and poor body conditions thus implying complexity of its etiology. Even after fairly good treatment of adult acnes, it is very likely that pigmentation occurs to produce freckles and also the affected skin surface is sometimes caved in to form acne crater at the site. The hormones that have drawn much attention as known to cause adult acnes are androgen, which secretes sebum through stimulation of sebaceous gland and estrogen, the antagonist of androgen. Where the balance of two hormones is disrupted, it results in secretion of excess sebum and acne is developed as a result.
A variety of pharmaceuticals have been developed as an effort to treat acnes, which include antibiotics such as erythromycin and benzoylperoxide to inhibit a proliferation of acne-causing bacteria and estrogen to regulate sebum secretion, however, most of which are generally associated with adverse effects. In cosmetics, vitamin A derivatives to remove keratin; and trichloric acid and salicylic acid to inhibit a proliferation of acne-causing bacteria have been developed and tested. However, these active ingredients exhibit a little effect but are usually associated with adverse effects such as skin flaring, skin hypersensitivity and light hypersensitivity. Further, the recurrence of acnes are usually observed when administered with these active ingredients. Consequently, there are not genuine products capable of preventing and treating acne.